504results about "Needle severing devices" patented technology

The invention provides a few-nest thread trimming control method, which is characterized in that a few-nest thread trimming mechanism is configured, the few-nest thread trimming mechanism comprises an auxiliary cutter, a movable cutter and a thread clamping assembly, and the movable cutter is provided with a sewing thread trimming cutting edge, a sewing thread hooking groove and an avoiding needle passing groove; in the first stitch of sewing, a machine needle penetrates through the sewing thread hooking groove, and an upper thread end on one side of the machine needle is brought to the position below the movable cutter; a first needle for starting sewing moves upwards, a movable cutter moves to enable an avoiding needle passing groove to be located under the needle, and a thread clamping assembly clamps an upper thread end; when the sewing machine starts to sew a second needle, a third needle,..., to an Nth needle, an upper thread end is cut off in the process of starting to sew the Nth needle, when the take-up-lever moves upwards to a target position A, the movable cutter moves towards the auxiliary cutter, the starting thread cutting edge and the auxiliary cutter are meshed to cut off the upper thread end, and the target position A is the non-highest point position of the take-up-lever; the take-up-lever continues to move upwards, the upper thread below the sewing material is drawn back, the bottom thread is tightened, the length of the bird nest is reduced, and few bird nests are sewn more reliably.

The invention provides a thread trimming method of a sewing machine, and belongs to the technical field of sewing machines. The problem that an existing thread trimming method is insufficient in bird groove preventing effect is solved. The thread trimming method comprises the following steps that A, a machine needle is driven to drive an upper thread end to move downwards to penetrate through a lower needle hole in a movable cutter and then move upwards to the position above a needle plate, and the upper thread end is kept in the lower needle hole; b, a thread trimming power mechanism starts to work, a movable cutter is driven to drive an upper thread end to move in the direction away from a needle falling hole, and then the thread trimming power mechanism stops working; c, the needle bar power mechanism drives the machine needle to sew a plurality of stitches; d, the thread trimming power mechanism works again, the movable cutter and the auxiliary cutter are driven to move in the direction close to the needle falling hole together, the movable cutter stops moving until the movable cutter is located under the needle falling hole in the needle plate, and the auxiliary cutter continues to move to be meshed with the movable cutter edge to cut off the upper thread end. The thread trimming device has the advantages of being high in thread trimming efficiency and good in bird nest prevention effect.

This invention provides a single-action anti-bird nest thread-cutting mechanism and its control method. The single-action anti-bird nest thread-cutting mechanism includes a fixed blade, a rotatable movable blade, a thread-cutting drive source, and a thread-cutting drive assembly. The fixed blade has a fixed blade edge. The thread-cutting drive source is connected to the movable blade via the thread-cutting drive assembly, driving the movable blade to rotate towards or away from the fixed blade. The movable blade has a starting thread hook groove and a separating thread hook groove. The starting thread hook groove allows the sewing machine needle to pass through. The movable blade has a moving blade edge on its surface facing the fixed blade. The starting thread hook groove and the separating thread hook groove are distributed on the same side of the moving blade edge. This application uses the same thread-cutting drive source and the same set of movable and fixed blades to achieve the purpose of preventing bird nests during the starting thread cutting and automatic thread cutting after sewing, effectively avoiding thread breakage during the starting thread and achieving a stable effect of normal starting thread without bird nest clumps.

The utility model provides a thread trimming mechanism and a sewing machine with the same. The thread trimming mechanism comprises a first movable cutter which comprises a thread clamping part and a first cutting edge part; the second movable cutter is arranged on one side of the first movable cutter, and the second movable cutter comprises a thread collecting groove and a second cutting edge part, and the thread collecting groove is used for allowing the upper threads to penetrate through; the second cutting edge part is located on the side, away from the first movable cutter, of the line concentration groove and faces a groove opening of the line concentration groove. The first cutting edge part is located on the side, away from the second movable cutter, of the thread clamping part and faces the thread clamping part. Wherein the second movable cutter is movably arranged in the direction close to or away from the first movable cutter so as to move to a thread clamping position where a clamping gap used for clamping an upper thread is formed between the thread clamping part and the second cutting edge part or a thread cutting position where the first cutting edge part and the second cutting edge part are in contact to cut off the upper thread. According to the technical scheme provided by the utility model, the technical problem that bird nest stitches are easily formed when a sewing machine in the prior art starts sewing can be solved.

The utility model provides a thread trimming structure of a sewing machine, and belongs to the technical field of sewing machines. The problems that an existing thread trimming structure is insufficient in working reliability and short in service life are solved. The thread trimming structure of the sewing machine comprises a thread pressing piece, an auxiliary cutter arranged on a machine base and a movable cutter which is located below a needle plate and can vertically swing around a rotating shuttle shaft of the sewing machine, the auxiliary cutter is provided with a thread trimming end with an auxiliary cutter edge, a thread hooking groove is formed in the movable cutter, and a movable cutter edge is formed in the upper edge of the thread hooking groove. When the movable cutter swings upwards, the thread hooking groove can directly face the needle falling hole up and down, when the movable cutter swings downwards, the cutting edge of the movable cutter can be meshed with the cutting edge of the auxiliary cutting edge, the thread pressing piece is movably connected to the upper side face of the movable cutter, and the movable cutter is further provided with a reset spring acting on the thread pressing piece. And when the auxiliary knife edge is meshed with the movable knife edge, the thread trimming end of the auxiliary knife can abut against the lower side face of the thread pressing piece. The working reliability and the service life of the thread trimming structure can be improved.

The present application provides a cloth feeding mechanism and a sewing machine for a sewing machine, specifically relating to the technical field of sewing machine manufacturing. The cloth feeding mechanism has a cloth feeding drive source and a lifter drive source. The cloth feeding drive source indirectly drives the tooth carrier of the cloth feeding mechanism. While the cloth feeding drive source indirectly drives the tooth carrier, the lifter drive source directly drives the same tooth carrier to generate a swinging motion. The tooth carrier and its cloth feeding teeth, under the combined action of the lifter drive source and the cloth feeding drive source, cause the cloth feeding teeth to perform a cloth feeding action. By using the cloth feeding drive source to indirectly drive the tooth carrier of the cloth feeding mechanism, and while the cloth feeding drive source indirectly drives the tooth carrier, the lifter drive source directly drives the same tooth carrier to generate a swinging motion, it is realized that the tooth carrier and its cloth feeding teeth, under the combined action of the lifter drive source and the cloth feeding drive source, cause the cloth feeding teeth to perform a cloth feeding action. The present application makes full use of the drive source of the sewing machine, effectively improves the utilization efficiency of the power of the sewing machine, greatly reduces the manufacturing cost of the sewing machine, and has high value for use and promotion.

The present invention provides a driving device for thread cutting, presser foot lifting and needle pitch adjustment, belonging to the technical field of sewing machines. It solves the problems such as reduced working efficiency of the existing device when meeting the requirements of driving thread cutting, presser foot lifting and needle pitch adjustment by one motor. The driving device for thread cutting, presser foot lifting and needle pitch adjustment includes a motor. A separately arranged thread cutting cam, a presser foot lifting cam and a needle pitch adjusting cam are fixedly connected to the rotating shaft of the motor. Both the thread cutting cam and the presser foot lifting cam are diamond-shaped, and the needle pitch adjusting cam is a curved quadrilateral. The needle pitch adjusting mechanism abuts against the outer peripheral wall of the needle pitch adjusting cam. When the effective needle pitch adjusting section of the needle pitch adjusting cam acts on the needle pitch adjusting mechanism, the thread cutting idle stroke surface of the thread cutting cam acts on the thread cutting mechanism, and the lifting idle stroke surface of the presser foot lifting cam acts on the presser foot lifting mechanism. This device meets the requirements of driving thread cutting, presser foot lifting and needle pitch adjustment by one motor and improves the working efficiency of the sewing machine at the same time.

The conductive thread embroidery proceeds from a first point outside a segmented area set on a sheet material to a second point on the segmented area. An embroidery with the conductive thread is sewn from the second point as a starting point to attach a segment in the segmented area. This series of steps is performed without performing a process for cutting the conductive thread by stopping the sewing process of the conductive thread.

The utility model relates to a machine head integrated cutter structure which comprises a machine shell and a mounting shell integrally formed on the machine shell, a first cavity and a second cavity are formed in the mounting shell, a sliding rod and a driving structure for driving the sliding rod to vertically slide are arranged on the first cavity in a sliding mode, and the top end of the sliding rod is located in the first cavity; the bottom end of the sliding rod downwards penetrates through the first cavity, and the cutter is installed at the bottom of the sliding rod. The driving structure comprises a motor, a sliding spring and a cam; the cam is rotationally connected to the inner wall of the first cavity, the axis of the cam is transverse, and the motor drives the cam to rotate; a sliding block is arranged at the top end of the sliding rod, the sliding spring is located between the sliding block and the inner wall of the first cavity and jacks up the sliding block, and the cam rotates to press the sliding block downwards to enable the cutter to cut the line. The second cavity is used for installing the presser foot mechanism and communicates with the first cavity, and the sliding rod is connected to the first cavity in a sealed and sliding mode. The cutter structure has the effect that the cutter structure is more convenient to lubricate.

The present invention proposes a sewing machine with stitch length adjustment and zero-position positioning of a swing seat, specifically relating to the technical field of sewing machine manufacturing, comprising a driving source, a connecting rod, and a swing seat, characterized in that it also comprises an adjusting wheel and a slider, wherein the driving source drives the slider on the output shaft to indirectly position the swing seat at zero, and the slider is arranged on a slide groove of the adjusting wheel, the adjusting wheel is connected to the connecting rod, and the connecting rod is hinged to the swing seat. The present application has the characteristics of high accuracy in positioning the zero point of the swing seat, the static positioning wheel is fixed and equipped with an adjusting wheel to make the operation more stable, the gap between the various components is small after positioning, the degree of mechanical wear of the various components is small, and the noise is relatively low, which has the advantages of stable operation and high promotion and use value.

The utility model relates to the technical field of lockstitch sewing machines, in particular to a combined mechanism for trimming threads and adjusting feed lifting amount of a lockstitch sewing machine and the lockstitch sewing machine. Comprising a thread trimming mechanism, a feed lifting amount adjusting mechanism and a first driving motor, and the first driving motor drives the thread trimming mechanism and the feed lifting amount adjusting mechanism; a rotating area of a motor shaft of the driving motor I can be at least divided into a thread trimming area and a feed lifting amount adjusting area; when the motor shaft rotates in the thread trimming area, the thread trimming mechanism executes a thread trimming action, and the feed lifting amount adjusting mechanism does not execute effective feed rack height adjustment; when the motor shaft rotates in the feed lifting amount adjusting area, the feed lifting amount adjusting mechanism adjusts the effective height of the feed rack, and the thread trimming mechanism does not execute the thread trimming action; the feed lifting amount adjusting mechanism comprises a feed lifting assembly, a feed lifting amount adjusting assembly and a feed lifting amount adjusting assembly, the combined assembly is simultaneously connected with the feed lifting assembly, the driving motor I and the upper shaft; the upper shaft transmits power to the feed lifting assembly through the combined assembly, and the first driving motor adjusts the transmission amplitude between the upper shaft and the feed lifting assembly through the combined assembly.

The utility model provides a swing mechanism in a sewing machine or a button sewing machine, and belongs to the technical field of sewing machines. The button sewing machine solves the problem of how to enable the moving precision of buttons on the button sewing machine to be high. And the like. According to the swing mechanism in the sewing machine or the button sewing machine, the sewing machine or the button sewing machine comprises a rack, a first power source and a swing bottom plate are arranged on the rack, the swing mechanism comprises a swing disc and a connecting rod assembly, the first power source is connected with the swing disc and can drive the swing disc to swing relative to the rack, a first through groove is formed in the swing disc, and a second through groove is formed in the connecting rod assembly. The inner end of the connecting rod assembly is hinged to the first through groove and can slide in the first through groove, and the outer end of the connecting rod assembly is connected with the swing bottom plate. The inner end of the connecting rod assembly is hinged into the first through groove, the first through groove plays a role in limiting swinging of the connecting rod assembly, the swinging precision of the swinging bottom plate is improved, and the moving precision of the button on the swinging bottom plate is improved.

The utility model discloses a trimming device for an upper pulling machine, which comprises an upper pulling machine main body, a fixed cutter group and a movable cutter group, the fixed cutter group and the movable cutter group are arranged on the upper pulling machine main body, the movable cutter group consists of a movable cutter group driving cylinder and a movable cutter group bearing, and the tail end of a piston rod of the movable cutter group driving cylinder is connected with a push arm. A middle connecting arm is hinged to the tail end of the push arm, a rotating frame is hinged to the tail end of the middle connecting arm, a clamping groove sleeve frame is connected and installed on the rotating frame, the movable cutter set bearing and the rotating frame are fixedly installed together, a clamping groove is formed in the side face of the clamping groove sleeve frame, and an arc-shaped movable blade is installed on the upper groove wall of the clamping groove. The feeding mechanism has the advantages that the feeding mechanism can be installed on an existing upper pulling machine structure, original upper pulling machine parts do not need to be replaced, a needle and thread assembly above the feeding wheel is not interfered, and the pushing connecting arm assembly is high in strength and durable.

The invention provides a thread trimming mechanism of a sewing machine, and belongs to the technical field of sewing machines. A thread trimming mechanism of a sewing machine comprises a fixed cutter; the movable cutter assembly is matched with the fixed cutter, can translate relative to the fixed cutter and is used for trimming threads; the driving assembly is used for driving the moving cutter assembly to move back and forth, the driving assembly comprises a swing rod, the swing rod can swing around a first axis, one end of the swing rod is movably connected with the moving cutter assembly, and the swing rod is further provided with a contact assembly; a thread trimming cam is fixed to the transmission shaft and makes contact with the contact assembly, so that the swing rod can swing in the direction away from the fixed cutter; a push rod of the pusher is connected with the lower end of the contact assembly, and the pusher is used for enabling the swing rod to swing towards the fixed cutter.

The utility model relates to the technical field of sewing equipment, in particular to a thread cutting mechanism of a sewing machine. The problems that an existing wire cutting mechanism is complex in structure, and debugging can be conducted only after all parts are installed in place in the debugging process are solved. The technical scheme adopted by the utility model comprises a movable cutter holder, the movable cutter holder is irregular, a groove is transversely formed in the upper surface of the movable cutter holder, the fixed cutter is fixedly arranged in the groove, sliding grooves allowing the movable cutter to slide are formed in the two side faces of the groove respectively, the upper surface of the movable cutter is fixedly arranged on the fixing plate, and the movable cutter is driven to slide in the sliding grooves through movement of the fixing plate. A right mounting plate and a left mounting plate are respectively arranged on the upper surface of the movable cutter seat on two sides of the fixed plate, a brake plate is arranged on the left mounting plate, a spring plate is arranged between the brake plate and the left mounting plate, and the other end of the spring plate is pressed on the movable cutter. The novel independent wire cutting mechanism is arranged, the structure is simpler, and the installation space is smaller. Maintenance is convenient, maintenance cost is reduced, and efficiency is improved.

Peripheral sewing equipment comprises a rack, a feeding platform is installed on the front side of the rack, a mechanical arm is installed on the feeding platform, and a sewing machine and a thread trimming device are installed on the rear side of the rack. A strip-shaped guide hole is formed in the surface of the feeding platform, a tray moving mechanism is arranged below the feeding platform and comprises a positioning plate, and a linear sliding table, a feeding electromagnetic mounting plate and a discharging electromagnetic mounting plate are fixedly mounted on the upper surface of the positioning plate. A movable positioning cylinder is slidably mounted on the linear sliding table through a movable plate; a feeding electromagnet and a discharging electromagnet are mounted on the feeding electromagnetic mounting plate and the discharging electromagnetic mounting plate respectively; a tool upper die plate is installed at the end of the mechanical arm, a tool lower die plate is arranged on the feeding platform, an upper die plate magnet corresponds to a lower die plate magnet, and an electromagnetic adsorption plate is arranged in the middle of the tool lower die plate. And a positioning through hole is formed in the surface of the tool lower template. According to the utility model, the defects in the prior art are overcome, the production efficiency can be greatly improved, and the sewing quality of cloth is also effectively improved.

The utility model belongs to the technical field of sewing machines, and particularly relates to a double-stepping overedger which comprises a machine body, and a thread trimming assembly, a presser foot lifting assembly, a feed lifting tooth shaft and a feeding tooth frame are arranged in the machine body. The first stepping motor is arranged on the side face of the machine body, a first motor shaft is arranged in the first stepping motor, and double cams are installed on the periphery of the first motor shaft and used for driving the thread trimming assembly and the presser foot lifting assembly to act; the second stepping motor is arranged on the side face of the machine body, a second motor shaft is arranged in the second stepping motor, a first crank is installed on the periphery of the second motor shaft, and one end of the first crank is connected with a connecting rod. The second stepping motor can control the height of the feeding tooth frame, the rotation angle of the stepping motor is utilized to enable the teeth to operate according to the set height, through double-stepping control, non-pneumatization and non-electromagnet are achieved, production noise can be lowered, and the sewing effect is improved.

The utility model provides a medium-speed industrial decorative edge overlock machine. The intermediate-speed industrial decorative edge overlock machine comprises an overlock plate, an overlock machine body is installed at the top of the overlock plate, a workbench is arranged on the overlock machine body, a cutting air cylinder is installed on the overlock machine body, a cutting telescopic column is slidably connected to the bottom of the cutting air cylinder, a cutting blade is fixedly connected to the bottom of the cutting telescopic column, and the cutting blade is fixedly connected to the bottom of the cutting telescopic column. A cutting protection sleeve is fixedly connected to the cutting air cylinder, a flow guide groove is formed in the top of the workbench, a passing groove is formed in the top of the overlock plate, a waste bin is arranged at the bottom of the overlock plate, a handle is fixedly connected to the waste bin, and two limiting sliding blocks are fixedly connected to the bottom of the overlock plate. A limiting sliding groove is formed in the top of the waste bin. The medium-speed industrial decorative edge overedger has the advantages of improving working efficiency and relieving labor burden of workers.

The utility model provides a trimming and presser foot lifting mechanism of a button sewing machine, which comprises a driving motor, a presser foot lifting driving block, a trimming driving block, a trimming blade and a button clamp block which are arranged in a machine shell, a driving cam is arranged on an output shaft of the driving motor, the presser foot lifting driving block and the trimming driving block both abut against the side face of the driving cam, and the button clamp block is arranged on the side face of the driving cam. When the driving motor drives the driving cam to rotate, the driving cam sequentially drives the thread trimming driving block and the presser foot lifting driving block to rotate, and the rotating thread trimming driving block and the rotating presser foot lifting driving block respectively drive the thread trimming blade and the button clamp block to sequentially rotate through linkage pieces. According to the trimming and presser foot lifting mechanism of the button sewing machine, the driving motor drives the driving cam to rotate, trimming and lifting are driven in a staggered mode, trimming is conducted firstly, then presser foot lifting is conducted, trimming thread ends are shorter, stitches are more attractive, the subsequent thread end trimming process does not need to be set, and therefore the production cost is reduced.

The invention discloses an upper thread sewing starting processing device and a sewing machine, and relates to the technical field of sewing machines, a needle plate assembly of the upper thread sewing starting processing device is provided with a needle plate hole, a thread grabbing plate and a thread clamping plate are movably assembled on the needle plate assembly, a thread trimmer is fixedly assembled on the needle plate assembly, the thread grabbing plate is provided with a thread grabbing hole, and the thread clamping plate is provided with a thread clamping head. The driving assembly is connected with the wire grabbing plate and the wire clamping plate and used for controlling the wire grabbing plate and the wire clamping plate to move. Wherein the moving route of the wire grabbing plate is a first route, and the moving route of the wire clamping plate is a second route; when the thread grabbing plate is located at the head end of the first route, the upper thread penetrates through the needle plate hole and the thread grabbing hole, and when the thread grabbing plate moves to the tail end from the head end of the first route, the upper thread is clamped by the thread clamping head and then cut off by the thread trimmer; when the thread clamping plate is located at the tail end of the second line, the thread clamping head loosens the upper thread. According to the upper thread sewing starting processing device, the upper thread can be clamped, cut off and loosened in one-time movement in the sewing starting stage, the movement process is simplified, and the sewing quality is improved.

The utility model relates to the technical field of bag sewing, and provides an automatic sewing machine for a zipper box, which is used for solving the problem of unsafety of manual flanging operation and comprises a rack, an operation table top is arranged on the rack, a sewing machine is arranged on the operation table top, and a sewing guide block is arranged on a machine base of the sewing machine. The sewing guide block is detachably arranged on a machine base of the sewing machine, a positioning protrusion is arranged at the position, located below a needle head of the sewing machine, of the sewing guide block in an upward protruding mode, a sewing channel is vertically formed in the positioning protrusion in a penetrating mode, and the front end face and the rear end face of the positioning protrusion are arc-shaped faces adapting to corners of an external extrusion frame. A flanging block is arranged on the side, close to the inner side face of the sewing machine body, of the sewing guide block, an arc-shaped turning face is arranged on the outer side face of the flanging block, a sewing opening is formed in the flanging block in an up-down penetrating mode, and a first driving structure is arranged on the rack.

The invention provides a thread trimming structure of a double-cam type sewing machine, and belongs to the technical field of sewing machines. The problem that an existing thread trimming structure is insufficient in anti-bird groove effect is solved. The thread trimming structure further comprises a movable cutter cam and an auxiliary cutter cam, the movable cutter cam and the auxiliary cutter cam are arranged in parallel in a spaced mode and fixedly connected to the driving shaft, and the working circumferential face of the movable cutter cam comprises a first concave arc section AB, a first convex arc section BC, a second concave arc section CD and a second convex arc section DA which are sequentially connected end to end. The first convex arc section BC is provided with a section of trimming arc surface concentric with the driving shaft; when the thread trimming arc surface on the movable cutter cam slides over the abutting part I, the movable cutter stops at the position where the cutting edge of the movable cutter is located under the needle falling hole; and in the process, a needle raising and thread trimming peach tip a on the auxiliary knife cam can slide over the abutting part II, so that the auxiliary knife moves towards the edge of the movable knife and is engaged with the edge of the movable knife. The device has the advantages of being stable in work and good in bird nest prevention effect.

The utility model relates to the technical field of bartacking machines, in particular to a combined driving mechanism of a bartacking machine and the bartacking machine. Comprising a thread sweeping mechanism used for executing a thread sweeping action; the presser foot lifting mechanism is used for executing a presser foot lifting action; the thread trimming mechanism is used for executing a thread trimming action; the driving motor is used for driving the thread sweeping mechanism, the presser foot lifting mechanism and the thread trimming mechanism to work; the thread sweeping mechanism comprises a thread sweeping action assembly, a thread sweeping mechanism and a thread sweeping mechanism, the transmission arm is used for being connected with the driving motor; the thread sweeping connecting rod is used for connecting the thread sweeping action assembly and the transmission arm, so that the driving motor can drive the thread sweeping action assembly to execute the thread sweeping action; the thread sweeping mechanism further comprises an independent driving assembly, and the independent driving assembly can independently drive the thread sweeping mechanism to work.

The utility model belongs to the technical field of sewing machine technologies, and relates to an anti-interference type multi-light-eye correlation structure and a sewing machine thereof, a thread trimming switch assembly is arranged on a machine head of the sewing machine, and a thread trimmer assembly is arranged in a machine shell. A plurality of light eyes electrically connected with an electric control module of the sewing machine are sequentially arranged in the cloth feeding direction of the sewing machine, and emitters and inductors of the light eyes are arranged on the machine shell and the thread trimming switch assembly respectively to form an up-down correlation structure. Wherein the inductor of at least one light eye is arranged on the thread trimming switch assembly, and the inductor of the adjacent light eye is arranged on the machine shell. According to the anti-interference type multi-light-eye correlation structure and the sewing machine with the anti-interference type multi-light-eye correlation structure, the effects of accurate control and short thread ends can be achieved.

The utility model provides a trimming device with a simple structure, which comprises a trimming mechanism, the trimming mechanism comprises scissors, a driving motor and a connecting rod assembly, the scissors comprise a first scissors and a second scissors which are hinged with each other, and one end of the first scissors is provided with a first transmission rod; a second transmission rod is arranged at one end of the second scissors, the connecting rod assembly comprises a driving arm arranged on the driving motor and a push rod capable of pushing the first transmission rod and the second transmission rod to reciprocate so as to drive the scissors to trim threads, and one end of the first transmission rod is rotationally connected with the first scissors; the second transmission rod is rotatably connected with the second scissors, and the other end of the first transmission rod and the other end of the second transmission rod are rotatably connected to the push rod. The thread trimming device is simple in structure and low in cost.

To achieve a thread cutter of a sewing machine which can easily achieve sharpness and holding power of a bobbin thread.SOLUTION: A thread cutter 100 of a sewing machine is capable of adjusting sharpness of thread cutting by adjusting a pressing force for pressing a pressing part 41a of a first plate piece 41 to a movable blade 30 by a pressing power adjustment part 67 adjusting deflection of the first plate piece 41, and capable of adjusting the holding power of a bobbin thread by adjusting a contact pressure for pressing a felt material 50 mounted on a holding part 42a of a second plate piece 42 to the movable blade 30 by a contact pressure adjustment part 68 adjusting deflection of the second plate piece 42. Thereby, each can be adjusted independently, and sharpness of thread cutting and holding power of the bobbin thread can be both achieved relatively easily.SELECTED DRAWING: Figure 1

The technical scheme belongs to the technical field of sewing machines, and particularly relates to a double-moving-cutter thread trimming sewing machine which comprises a rack, a thread trimming mechanism and a rotating shuttle mechanism. The thread trimming mechanism comprises a first movable cutter assembly, a second movable cutter assembly and a driving assembly; the first movable cutter assembly and the second movable cutter assembly are rotationally arranged on the outer side of the matched rotating shuttle mechanism in a sleeving mode. The driving assembly drives the first movable cutter assembly to rotate between a first position and a second position around the axis and drives the second movable cutter assembly to move between a third position and a fourth position around the rotating axis. The first movable cutter assembly comprises a first thread trimming movable cutter, and the first thread trimming movable cutter is provided with a thread hole groove allowing a machine needle to penetrate through and hooking a sewing thread in the sewing starting stage and a first thread hooking groove allowing the sewing thread to be hooked in the ending stage; the second movable cutter assembly comprises a second thread trimming movable cutter; the thread hole groove or the first thread hooking groove hooks the sewing thread, the second thread trimming movable cutter is driven to rotate around the axis to abut against the surface of the first thread trimming movable cutter, the cutting edges of the two thread trimming movable cutters coincide to cut off the sewing thread, thread ends are reduced, and production efficiency is improved.

The invention relates to an operation control method for sewing a small nest by a sewing machine, which comprises the following working processes: a thread trimming working process: a main shaft rotates, a movable cutter extends out when the rotation angle is beta1, and the movable cutter reaches a thread trimming extending position when the rotation angle is beta2; when the main shaft rotates, the movable cutter stops at the trimming extension position, the take-up lever ascends, and the rotating angle of the main shaft is beta 3, the movable cutter begins to reset to hook the bottom thread and the upper thread; when the rotation angle of the main shaft is beta 4, the take-up lever ascends to the position Z1, the movable cutter returns to the initial position, the upper thread and the bottom thread are cut off, and the bottom thread is clamped; in the seam starting working process, the main shaft rotates, the suction opening generates a suction effect, and the movable cutter extends out; the movable cutter reaches a seam starting extending position; the movable cutter is fixed, the machine needle descends to penetrate through the cutter part through hole and then ascends, and the take-up lever ascends; when the take-up lever ascends to the position Z2, the movable cutter retreats; the movable cutter reaches the initial position and keeps still, the upper thread is cut off, and the upper thread is clamped; continuously rotating the main shaft for two cycles to form two stitches; and the adsorption assembly stops.

The utility model discloses a thread trimming device of a sewing machine and the sewing machine with the thread trimming device, which belong to the technical field of sewing machine accessories, and comprise a blade, a first-stage oscillating bar mechanism, a second-stage oscillating bar mechanism, a third-stage oscillating bar mechanism and a telescopic component which are arranged in a panel of the sewing machine and are connected in sequence, the first-stage oscillating bar mechanism, the second-stage oscillating bar mechanism, the third-stage oscillating bar mechanism and the telescopic component are all connected with the sewing machine panel; the blade is arranged on one side above a bobbin case in the sewing machine panel; the sewing machine comprises a machine head and a sewing machine panel, the thread trimming device is installed in the sewing machine panel, and the blade is arranged on the lower right portion of feed dogs at the end of the sewing machine panel. The telescopic component drives the first-stage swing rod mechanism, the second-stage swing rod mechanism and the third-stage swing rod mechanism to drive the blade to swing, a sewing thread between a machine needle and a bobbin case can be cut off after sewing is finished, the downtime is shortened, the working efficiency is improved, and the labor intensity of workers is reduced; and the original sewing machine can be reformed, so that the production cost is reduced.

The utility model relates to the technical field of sewing equipment, in particular to an improved thread trimming mechanism of a sewing machine, which comprises a thread trimming structure, and the thread trimming structure comprises a movable cutter unit and a fixed cutter matched with the movable cutter unit for use; the movable cutter unit comprises a driving part, an annular supporting seat, a mounting part integrally formed with the annular supporting seat and a cutter, the cutter is mounted on the mounting part through a fastener, a first blade part is arranged on the cutter, and a second blade part meshed with the first blade part is arranged on the fixed cutter; the driving piece drives the annular supporting base to rotate so as to drive the first blade part of the cutter to approach the second blade part of the fixed cutter to cut off the thread residues. According to the thread trimming structure, the complex structure of a traditional thread trimming mechanism is simplified, and the manufacturing and maintenance cost is reduced. Meanwhile, the conveying mechanism is composed of a first gear, a second gear and a conveying belt, belt conveying transmits power through friction or synchronous gear meshing, instant impact force can be effectively reduced, and the problems of vibration and noise caused by rigid transmission are solved.